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BS_(0.5)BNT-based relaxor ferroelectric ceramic/glass-ceramic composites for energy storage

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Journal of Advanced Ceramics 2023年第4期12卷 695-710页

作者： Xuhai Shi Kai Li Zong-Yang Shen Junqi Liu Chaoqun Chen Xiaojun Zeng Bo Zhang Fusheng Song Wenqin luo zhumei Wang Yueming Li China National Light Industry Key Laboratory of Functional Ceramic Materials Energy Storage and Conversion Ceramic Materials Engineering Laboratory of Jiangxi ProvinceAdvanced Ceramic Materials Research InstituteSchool of Materials Science and EngineeringJingdezhen Ceramic UniversityJingdezhen 333403China

Relaxor ferroelectric ceramics have very high dielectric constant(e)but relatively low electrical breakdown strength(Eb),while glass-ceramics exhibit higher E,due to the more uniformly dispersed amorphous phases and submicrocrystals/nanocrystals inside.How to effectively combine the advantages of both relaxor ferroelectric ceramics and glass-ceramics is of great significance for the development of new dielectric materials with high energy storage performance.In this work,we firstly prepared BaO-SrO-Bi_(2)O_(3)-Na_(2)0-TiO_(2)-Al_(2)O_(3)-SiO_(2)(abbreviated as GS)glass powders,and then fabricated(Ba_(0.3)Sr_(0.7))_(0.5)(Bi_(0.5)Na_(0.5))_(0.5)TiO_(3)+x wt%GS ceramic composites(abbreviated as BSo.sBNT-xGS,x=0,2,6,10,14,16,and 18).Submicrocrystals/nanocrystals with a similar composition to BSo.sBNT were crystalized from the glass,ensuring the formation of uniform core-shell structure in BSo.sBNT-xGS relaxor ferroelectric ceramic/glass-ceramic composites.When the addition amount of GS was 14 wt%,the composite possessed both high&r(>3200 at 1 kHz)and high E,(~170 kV/cm)at room temperature,and their recoverable energy storage density and efficiency were Wrec=2.1 J/cm’and n=65.2%,respectively.The BSo.sBNT-14GS composite also had several attractive properties such as good temperature,frequency,cycle stability,and fast charge-discharge speed.This work provides insights into the relaxor ceramic/glass-ceramic composites for pulsed power capacitors and sheds light on the utilization of the hybrid systems.

关键词： relaxor ferroelectrics energy storage ceramics glass-ceramics Bi_(0.5)Na_(0.5)TiO_(3)(BNT) Ba_(0.3)Sr_(0.7)TiO_(3)(BST)

P-E hysteresis loop going slim in Ba0.3Sr0.7TiO3-modified Bi0.5Na0.5TiO3 ceramics for energy storage applications

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Journal of Advanced Ceramics 2020年第2期9卷 183-192页

作者： Dongxu LI Zong-Yang SHEN Zhipeng LI Wenqin luo Xingcai WANG zhumei WANG Fusheng SONG Yueming LI Energy Storage and Conversion Ceramic Materials Engineering Laboratory of Jiangxi Province China National Light Industry Key Laboratory of Functional Ceramic MaterialsSchool of Materials Science and EngineeringJingdezhen Ceramic InstituteJingdezhen333000China Chengdu Hongke Electronic Technology Co. Ltd.Chengdu610000China

(Ba0.3Sr0.7)x(Bi0.5Na0.5)1-xTiO3(BSxBNT,x=0.3–V0.8)ceramics were prepared to investigate their structure,dielectric and ferroelectric properties.BSxBNT ceramics possess pure perovskite structure accompanied from a tetragonal symmetry to pseudo-cubic one with the increase of x value,being confirmed by X-ray diffraction(XRD)and Raman results.The Tm corresponding to a temperature in the vicinity of maximum dielectric constant gradually decreases from 110℃(x=0.3)to-45℃(x=0.8),across Tm=36℃(x=0.5)with a maximum dielectric constant(ɛr=5920@1 kHz)around room temperature.The saturated polarization Ps gradually while the remnant polarization Pr sharply decreases with the increase of x value,making the P-E hysteresis loop of BSxBNT ceramics goes slim.A maximum difference between Ps and Pr(Ps-Pr)is obtained for BSxBNT ceramics with x=0.5,at which a high recoverable energy density(Wrec=1.04 J/cm3)is achieved under an applied electric field of 100 kV/cm with an efficiency ofη=77%.Meanwhile,the varied temperature P-E loops,fatigue measurements,and electric breakdown characteristics for the sample with x=0.5 indicate that it is promising for pulsed power energy storage capacitor candidate materials.

关键词： energy storage ceramics Ba0.3Sr0.7TiO3(BST) Bi0.5Na0.5TiO3(BNT) relaxor ferroelectrics pulsed power capacitor

上游扰动条件下尾水管涡带演化和压力脉动研究

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农业机械学报 2022年第6期53卷 192-201页

作者：郭涛徐李辉罗竹梅昆明理工大学建筑工程学院昆明650500 昆明理工大学能源与动力工程系昆明650093

尾水管涡带是混流式水轮机流动不稳定的表征,严重时甚至会导致机组疲劳破坏。为准确捕捉不同工况下尾水管内流体流动的瞬态湍流特性,采用滑移网格技术以及SST kω湍流模型,通过现阶段最新进展的Liutex涡识别方法对尾水管涡带进行捕捉并... 详细信息

尾水管涡带是混流式水轮机流动不稳定的表征,严重时甚至会导致机组疲劳破坏。为准确捕捉不同工况下尾水管内流体流动的瞬态湍流特性,采用滑移网格技术以及SST kω湍流模型,通过现阶段最新进展的Liutex涡识别方法对尾水管涡带进行捕捉并对比分析,着重分析了不同来流对尾水管涡带的形成、发展、破裂和低频压力脉动的影响。结果表明:与文献实验结果的对比,验证了结果的准确性;上游不同来流条件下,尾水管涡带形态各异。最优工况时仅形成一个稳定的旋流结构,即纺锤形涡带,对流场影响较小。流量降低到设计流量的81%时,形成螺旋形涡带,涡带的偏心运动对主流产生了较大干扰作用,涡流、回流和流动分离等不稳定现象明显。由于涡带对主流的排挤作用,造成涡带与壁面之间出现明显的高速区,平均脉动压力系数幅值也比最优工况增加了1.36~4倍,压力脉动呈现出典型的低频、高幅特征;随着开度的继续降低,涡带体积大幅度增加,形成一个较大的空腔涡带,占据流域范围较广,与肘管壁面发生直接“冲击现象”;开度越小尾水管内产生的涡流越杂乱,流场越不稳定,当开度降至最低时,有形涡带消失,破碎后的杂涡充据着整个直锥段和弯肘段。

关键词：混流式水轮机尾水管涡带上游扰动压力脉动

Ce and W co-doped CaBi_(2)Nb_(2)O_(9) with enhanced piezoelectric constant and electrical resistivity at high temperature

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Journal of Materiomics 2020年第3期6卷 459-466页

作者： Zong-Yang Shen Chen Qin Wen-Qin luo Fusheng Song zhumei Wang Yueming Li Shujun Zhang Energy Storage and Conversion Ceramic Materials Engineering Laboratory of Jiangxi Province China National Light Industry Key Laboratory of Functional Ceramic MaterialsSchool of Materials Science and EngineeringJingdezhen Ceramic InstituteJingdezhen333403China Institute for Superconducting and Electronic Materials Australian Institute of Innovative MaterialsUniversity of WollongongWollongongNSW2500Australia

Ce and W co-doped CaBi_(2)Nb_(2)O_(9) ceramics with chemical formula Ca_(0.96)Ce_(0.04)Bi_(2)Nb_(2-x)W_(x)O_(9)(CCBNW100x,x=0-0.07)are fabricated via conventional solid state sintering method,to investigate the effect of W addition on the structure,electrical resistivity,dielectric and piezoelectric properties.A piezoelectric constant d33 of 13.4 pC/N is obtained in CCBN-W2 ceramics,>100% higher than that of pure CaBi_(2)Nb_(2)O_(9)(d_(33)=5.8e6.4 pC/N).Of particular significance is that the electrical resistivity of CCBN-W2 ceramics(r=3.7×109 U cm at 500℃)is three orders of magnitude higher than pure CaBi_(2)Nb_(2)O_(9)(r=2.9×10^(6) U cm at same temperature).All these properties,together with its low dielectric loss(tandδ0.13%)and excellent d33 thermal stability up to 800℃,merit the CCBN-W2 ceramics for high temperature piezoelectric sensing applications.

关键词： Ultra-high temperature ceramics Piezoelectric properties Aurivillius phase Bismuth layered structure CaBi_(2)Nb_(2)O_(9)

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涡激振动驱动的柱群结构集中俘获海流能研究

太阳能学报 2021年第4期42卷 89-94页

作者：罗竹梅聂聪郭涛昆明理工大学能源与动力工程系昆明650093 昆明理工大学工程力学系昆明650500

采用一种结合串列、并列和错列布置的耦合连接五圆柱柱群结构为能量转换器,在不同间距比不同约化速度下,以流固双向耦合数值算法对其进行涡激振动模拟和计算分析。通过对比相同参数条件下单圆柱俘能结构的结果,获得柱群俘能结构集中俘... 详细信息

采用一种结合串列、并列和错列布置的耦合连接五圆柱柱群结构为能量转换器,在不同间距比不同约化速度下,以流固双向耦合数值算法对其进行涡激振动模拟和计算分析。通过对比相同参数条件下单圆柱俘能结构的结果,获得柱群俘能结构集中俘获低速海流能的初步理论。结果显示:在产生共振的约化速度范围内,较大间距比下的柱群俘能结构其振幅和各圆柱压力分布特征与单圆柱俘能结构相似;总升力谱峰值约为单圆柱的3倍;从俘能大小来看,相同约化速度下俘获的水动能P达到单圆柱的4~5倍。研究结果说明共振范围内,柱群俘能结构在较大组合间距比时可集中俘获低速海流能。

关键词：海流能俘能流固耦合涡激振动水动能

Remarkably enhanced dielectric stability and energy storage properties in BNT–BST relaxor ceramics by A-site defect engineering for pulsed power applications

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Journal of Advanced Ceramics 2022年第2期11卷 283-294页

作者： Zhipeng LI Dong-Xu LI Zong-Yang SHEN Xiaojun ZENG Fusheng SONG Wenqin luo Xingcai WANG zhumei WANG Yueming LI Energy Storage and Conversion Ceramic Materials Engineering Laboratory of Jiangxi Province China National Light Industry Key Laboratory of Functional Ceramic MaterialsSchool of Materials Science and EngineeringJingdezhen Ceramic UniversityJingdezhen 333403China State Key Laboratory of Advanced Technology for Materials Synthesis and Processing School of Materials Science and EngineeringWuhan University of TechnologyWuhan 430070China Chengdu Hongke Electronic Technology Co. Ltd.Chengdu 610000China

Lead-free bulk ceramics for advanced pulsed power capacitors show relatively low recoverable energy storage density(Wrec)especially at low electric field condition.To address this challenge,we propose an A-site defect engineering to optimize the electric polarization behavior by disrupting the orderly arrangement of A-site ions,in which Ba_(0.105)Na_(0.325)Sr_(0.245−1.5x)□_(0.5x)Bi_(0.325)+xTiO_(3)(BNS_(0.245−1.5x)□_(0.5x)B_(0.325+x)T,x=0,0.02,0.04,0.06,and 0.08)lead-free ceramics are selected as the representative.The BNS_(0.245−1.5x)□_(0.5x)B_(0.325+x)T ceramics are prepared by using pressureless solid-state sintering and achieve large W_(rec)(1.8 J/cm^(3))at a low electric field(@110 kV/cm)when x=0.06.The value of 1.8 J/cm3 is super high as compared to all other W_(rec) in lead-free bulk ceramics under a relatively low electric field(<160 kV/cm).Furthermore,a high dielectric constant of 2930 within 15%fluctuation in a wide temperature range of 40–350℃is also obtained in BNS_(0.245−1.5x)□_(0.5x)B_(0.325+x)T(x=0.06)ceramics.The excellent performances can be attributed to the A-site defect engineering,which can reduce remnant polarization(P_(r))and improve the thermal evolution of polar nanoregions(PNRs).This work confirms that the BNS_(0.245−1.5x)□_(0.5x)B_(0.325+x)T(x=0.06)ceramics are desirable for advanced pulsed power capacitors,and will push the development of a series of Bi0.5Na0.5TiO3(BNT)-based ceramics with high W_(rec) and high-temperature stability.

关键词： relaxor ferroelectrics energy storage ceramics ceramic capacitor Bi_(0.5)Na_(0.5)TiO_(3)(BNT) defect engine

Glass modified barium strontium titanate ceramics for energy storage capacitor at elevated temperatures

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Journal of Materiomics 2019年第4期5卷 641-648页

作者： Zong-Yang Shen Yu Wang Yanxue Tang Yuanying Yu Wen-Qin luo Xingcai Wang Yueming Li zhumei Wang Fusheng Song Energy Storage and Conversion Ceramic Materials Engineering Laboratory of Jiangxi Province China National Light Industry Key Laboratory of Functional Ceramic MaterialsSchool of Materials Science and EngineeringJingdezhen Ceramic InstituteJingdezhen333403China Key Laboratory of Optoelectronic Material and Device Shanghai Normal UniversityShanghai200234China Chengdu Hongming UESTC Electronic New Materials Co. Ltd.Chengdu610100China

A glass with composition of B_(2)O_(3)-Bi_(2)O_(3)-SiO_(2)-CaO-BaO-Al_(2)O_(3)-ZrO_(2)(BBSZ)modified Ba_(x)Sr_(1-x)TiO_(3)(BST,x=0.3 and 0.4)ceramics were prepared by a conventional solid state reaction method abided by a formula of BST+y%BBSZ(y=0,2,4,7,and 10,in mass).The effect of BBSZ glass content on the structure,dielectric properties and energy storage characteristics of the ceramics was investigated.The dielectric constant reduced but the endurable electrical strength enhanced due to the BBSZ glass addition in BST ceramics.In particular,the dielectric loss of the ceramics at elevated temperature(e.g.200℃)can be strongly suppressed from tanδ>20%to tanδ<3% after BBSZ glass modification.For Ba_(0.3)Sr_(0.7)TiO_(3)+2%BBSZ ceramics,an optimized energy storage density(γ=0.63 J/cm^(3))and efficiency(η=91.6%)under an applied electric field of 160 kV/cm was obtained at room temperature.Meanwhile,the temperature dependent polarization-electric field(P-E)hysteresis loops were measured to evaluate the energy storage characteristics of the ceramics potential for high voltage capacitor application at elevated temperatures.

关键词： Barium strontium titanate Glass modification Energy storage Ceramic capacitor

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农业产业化龙头企业价值链融资担保机制研究

黑河学院学报 2017年第9期8卷 54-55,101页

作者：骆竹梅浙江广厦建设职业技术学院浙江东阳322100

我国传统的经济结构让农业融资产生困难,为了让农业产业化企业获得信贷,各大金融机构向农业产业化龙头企业提供了足够的担保。担保制度的不完善,成为制约现代农村经济发展的重要条件,农业生产企业的经济发展由于缺乏有效的担保资产,提... 详细信息

我国传统的经济结构让农业融资产生困难,为了让农业产业化企业获得信贷,各大金融机构向农业产业化龙头企业提供了足够的担保。担保制度的不完善,成为制约现代农村经济发展的重要条件,农业生产企业的经济发展由于缺乏有效的担保资产,提高了贷款发生风险的系数。这就出现了农业生产企业"难贷款"、农民"贷款难"的被动局面。近年来,我国一些政府职能部门针对农业经济的发展特色,设立了一些适合农业生产企业发展的信贷担保机构,改善农业生产企业和农民信贷难的问题。而且对农村信贷担保机制创新问题进行了有效的研究,这些研究促进了我国担保创新机制的发展,对解决融资担保难问题具有现实意义,促使一些金融单位更好地为农业产业化企业服务。

关键词：农业产业融资担保龙头企业

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间距比对圆柱系统从水流中获取能量的影响

排灌机械工程学报 2014年第1期32卷 51-55页

作者：罗竹梅张立翔昆明理工大学冶金与能源工程学院云南昆明650093 昆明理工大学土木工程学院云南昆明650051

对均匀来流下由5个圆柱交错布置且两端刚性连接的圆柱系统的涡激振动进行了模拟,采用流固双向耦合数值方法,通过流固耦合求解器同时耦合求解流体模型和结构模型.对流速分别为0.5,0.6和0.7 m/s下,进行不同横向和流向间距比的计算,以分析... 详细信息

对均匀来流下由5个圆柱交错布置且两端刚性连接的圆柱系统的涡激振动进行了模拟,采用流固双向耦合数值方法,通过流固耦合求解器同时耦合求解流体模型和结构模型.对流速分别为0.5,0.6和0.7 m/s下,进行不同横向和流向间距比的计算,以分析间距比对由圆柱系统利用涡激振动从低速水流中获取能量及能量密度的影响.计算结果表明:在小间距比下,圆柱后无明显的涡脱落,圆柱系统振幅响应很小;但当间距比较大时,各圆柱后出现频率一致的泻涡,圆柱系统获得较大的振幅响应.获取能量随组合间距比的增大先增长较快,但当流向间距比L/D≥6,横向间距比H/D≥4时,获取能量值趋于稳定;当L/D=6,H/D=4时,能量密度在3个流速下都出现了最大值.因此选择L/D=6,H/D=4为合理的组合间距比,此时圆柱系统可从水流中充分获取能量.文中结论可作为流体机械振动系统的设计参考.

关键词：圆柱系统涡激振动流固双向耦合间距比